Currently Windsor-Essex and Chatham-Kent are the only areas not under threat of an ice storm but they do have a statement issued for heavy rain this weekend.
Environment Canada says the ice storm pelting parts of southern Ontario could be "historic", potentially downing trees and power lines and leading to widespread power outages.
Today's weather prediction of freezing rain and ice into the overnight hours has prompted one Onondaga County school district to make changes to tonight's scheduled prom.
A freezing rain warning is in place for Peterborough and southern Peterborough County, Lindsay and southern Kawartha Lakes, and Northumberland County, with an ice storm forecast for Sunday.
Snow or ice pellets will end in the evening then it will be cloudy with blowing snow.
Freezing rain may become mixed with or turn over to ice pellets at times in some areas, and Environment Canada says some snow is possible, especially in the Belleville to Kingston areas.More news: Dockless bike sharing service JUMP gets acquired by Uber
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"Precipitation may start out as rain, but increasing northeasterly winds will draw colder air from an arctic high pressure system to the north, resulting in a changeover to freezing rain".
Roads and highways could become quite slippery and flooding is possible.
The weather agency says the region is expected to get around 25-30 mm of rain over the weekend, which is about half of the month's average rainfall.
Watch for quickly changing road conditions from wet to icy this afternoon and evening.
For Monday, expect periods of rain or snow a high of 4 C.
People can report hydro outages by calling Alectra Utilities at 1-844-797-7920 in Brampton and 905-273-7425 in Mississauga.